<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>获取标签元素的属性值（复选框操作）</title>
</head>
<body>
    ⽤⼾名：<input type="text" name="user_name">
    密码：<input type="password" name="pwd">


    <input type="checkbox" name="Java">Java
    <input type="checkbox" name="Python">Python
    <input type="checkbox" name="C++">C++
    <input type="checkbox" name="JavaScript">JavaScript
    <input type="checkbox" name="HTML">HTML

     编程语⾔:
        <select>
            <option>Java</option>
            <option>C++</option>
            <option value="Python">Python</option>
            <option>HTML</option>
            <option>JavaScript</option>
        </select>

        <input type="button" id="alert" value="alert弹窗" onclick="alert('这是alert()弹窗!')">
        <input type="button" id="confirm"value="confirm弹窗" onclick="confirm('这是confirm()弹窗！')" >
        <input type="button" id="prompt" value="prompt弹窗" onclick="prompt('这是prompt()弹窗！','这是prompt()弹窗的默认值！')">
</body>
</html>